Superman Movieverse Forum

For a possible plot point in a future Supergirl story I need to know if Krypton's moon(s) were anything like as big as ours; did Krypton have tides etc.?

I don't seem to have anything that would shed much light on this - Wikipedia says two moons, one of which was destroyed by a Kryptonian supervillain, but doesn't give sizes etc. The Superman Wiki has a picture (from an animated episode) that shows two implausibly large moons, but they're so big that I have trouble imagining how they can possibly be in stable orbits. There isn't any data on orbital periods etc.

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Is there any source that gives sizes, orbital periods, etc., e.g. for one of the Superman RPGs?

Not very keen on that  - I'll have to check with an astronomer I know, but it feels like their gravitational pull on each other and tidal forces from the sun and Krypton would really mess things up if they were in orbits that similar.

Actually they're pretty big - more than twice the diameter of Ceres (which is classed as a dwarf planet) and more than half the diameter of Earth's moon, which is ridiculously large compared to the size of the Earth by most astronomical standards. This isn't necessarily a problem if there was just one, but two so close together is hugely unlikely.

Someone has also pointed out an error in the mass - they should be less than 0.01 Earth masses, not 0.2 and 0.25. Mass compared to Earth's moon, perhaps?

Sorry, the actual result is about 15% of the mass of Earth's moon, or about .002 earth masses.

That's still too high, I think - I'm pretty sure I didn't help, for some reason I was mixing up the moon's radius and diameter,  they are about 1/3rd its size so should be 1/27th its mass. Some evenings I REALLY shouldn't think about technical stuff, my brain is too tired...